This is an SDK for creating Spin apps using Python.

Note that this SDK supersedes an earlier, experimental version, which may be found in the old-sdk branch. (The old template remains on main temporarily to preserve compatibility for some inbound links; it will be removed or replaced.)

• Python 3.10 or later and pip
• componentize-py
• spin-sdk
• MyPy
  • This is optional, but useful for during development.
• Spin 2.2 or later.
  • As of this writing Spin 2.2 has not yet been released, so we must use the main branch of Spin for the time being. You can find pre-built binaries here.

Once you have Python and pip installed, you can use the latter to create and enter a virtual environment and then install the desired packages

python -m venv .venv
source .venv/bin/activate
pip install componentize-py==0.11.2 spin-sdk==2.0.0rc2 mypy==1.8.0

A minimal app requires two files: a spin.toml and a Python script, which we'll name app.py:

cat >spin.toml <<EOF
spin_manifest_version = 2

[application]
name = "hello"
version = "0.1.0"
authors = ["Dev Eloper <dev@example.com>"]

[[trigger.http]]
route = "/..."
component = "hello"

[component.hello]
source = "app.wasm"
[component.hello.build]
command = "componentize-py -w spin-http componentize app -o app.wasm"
EOF

cat >app.py <<EOF
from spin_sdk import http
from spin_sdk.http import Request, Response

class IncomingHandler(http.IncomingHandler):
    def handle_request(self, request: Request) -> Response:
        return Response(
            200,
            {"content-type": "text/plain"},
            bytes("Hello from Python!", "utf-8")
        )
EOF

Once you've created those files, you can check, build, and run your app:

python -m mypy app.py
spin build -u

Finally, you can test your app using e.g. curl in another terminal:

curl -i http://127.0.0.1:3000

If all goes well, you should see:

HTTP/1.1 200 OK
content-type: text/plain
transfer-encoding: chunked
date: Tue, 09 Jan 2024 18:26:52 GMT

Hello from Python!

Please file an issue if you have any trouble.

See the examples directory in the repository for more examples.